Databases Flashcards
1
Q
How do you delete a database?
A
“DROP”
2
Q
Which operator allows you to specify multiple values in a WHERE clause?
A
“IN”
3
Q
Which operator selects values without a given range?
A
“BETWEEN”
4
Q
Which operator returns TRUE if any of the sub query values meet the condition?
A
“ANY”
5
Q
Which operator is used to test for the existence of any record in a subquery?
A
“EXISTS”
6
Q
Which operator is used to display a result where a condition is not true?
A
“NOT”
7
Q
What are the two types of participation in an entity?
A
Mandatory and Optional
8
Q
What is a weak entity?
A
A table which uses a compound key rather than its own primary key.
9
Q
How are weak entities shown in ER diagrams?
A
A double rectangle rather than a single one
- A dotted line is used to connect a weak entity to the strong entity it relies on.
